Ladders, especially extension ladders, have had anti-sway devices attached to the upper ends thereof but they are usually clumsy and made in one piece, and are generally complicated.
A search of the patent files was conducted in Class 182, Subclasses 106, 173, 177, 229, 230 and 214, and the most pertinent art developed was:
U.s. pat. No. 2,993,562 to Hussey, 7/61 PA1 U.s. pat. No. 3,288,249 to Gibson, 11/66 PA1 U.s. pat. No. 3,653,462 to Courtney, 4/72 PA1 U.s. pat. No. 3,568,801 to Werner, 3/9/71
All these patents fall in the category expressed hereinabove.